nutch

http://www.cnblogs.com/clarkchen/archive/2011/03/10/1980194.html

http://www.cnblogs.com/freebsd-pann/archive/2011/11/08/2238163.html

http://www.cnblogs.com/jingmoxukong/p/4433945.html

 http://blog.csdn.net/bg_data/article/details/43668985

http://blog.csdn.net/jediael_lu/article/details/43086439